EP2269492A1 - Mixing tool for mixing bowls - Google Patents

Abstract

The tool (10) has a hub part (11) rotated at a drive axis in a rotation direction, and mixing arms (20, 30) radially extending from the hub part to the drive axis and comprising impact surfaces (22). The mixing arms exhibit inclination surfaces (28) adjacent to the impact surfaces. One inclination surface is aligned upwardly to the one mixing arm, and other inclination surface is aligned downwardly to the other mixing arm. The latter mixing arm is arranged higher than the former arm. Impact direction is changed over a length of the impact surfaces at more than 90 degree or 100 degree. An independent claim is also included for a method for beating dough with a mixing tool.

Description

Field of the invention

The present invention relates to a stirring tool, preferably for a food processor. For example, the stirring tool in a standard device (which is typically connected to a mixing bowl) can be used. It can be used with great advantage in mixing bowls or Teigtrögen. It can also be used in a hand mixer. In particular, it is also suitable for use with the drive unit of a blender. The stirring tool should be suitable for stirring cake, bread or pizza dough, but also for whipping cream and for crushing tasks, such as those incurred during stirring.

Background of the invention

For food processors, but also for other mixing, stirring and crushing tasks a variety of stirring tools is known.

US 2006/0062079 A1 (Applicant: Ekato Solidmix GmbH) discloses a stirrer with two adjustable arms for use in a trough. This stirring tool can be supplemented by a comminution tool. The mechanical construction is demanding. The additional use of a crushing tool seems rather expensive.

EP 1982624 A1 (Electrodomesticos Taurus SL) discloses a kitchen tool, especially for a blender. This tool should have three or more blades and be made of metal. The blades are oriented in different angular directions to promote the mixing of food in a stirred pot. Apart from their orientation, the blades are essentially of simple symmetrical shape. Therefore, it seems unlikely that a stirring result could be achieved which would be sufficient for about to stir cake dough.

US 2,193,686 (Craddock) discloses a stirring tool with substantially propeller-shaped stirring blades, which additionally have certain claws or webs. Although this stirring tool may perform its task effectively, but is demanding in the production and can probably be made only of metal, to have sufficient stability in its complicated shape.

EP 193128 A2 (SEB SA) discloses a tool which is particularly useful for the preparation of jams. The stirring tool shows relatively large stirring blades. An agitating blade is aligned in the direction of rotation and one opposite to the direction of rotation. The mixing paddles are tailored to a mixing bowl to be used. With another mixing bowl, the stirring tool is obviously bad or impossible to use. Due to the size of the stirring blades, a considerable torque is required to achieve both sufficient mixing and crushing of fruits and the like.

The present invention seeks to obviate the weaknesses of the prior art. In particular, a good mixing and solid batter with a simple and inexpensive to produce tool should be possible. This tool should also be usable with kitchen machines, which can not provide high torque.

This object is achieved by a stirring tool according to claim 1.

Main features of the invention

The present invention relates to a stirring tool, preferably for a food processor. In particular, it relates to a stirring tool, with a hub part rotatable about a drive axis in a direction of rotation, from which at least two stirring arms extend radially to the drive axis, each having a striking surface, wherein the stirring arms then each have an inclined surface on the striking surface and this inclined surface the first stirring arm is oriented upward and the inclined surface is aligned on the second Rührarm down. Furthermore, the invention relates to a motor-driven kitchen appliance and a method for whipping dough with such a stirring tool.

Detailed description of the invention

According to the invention, the stirring tool thus has a hub part which is rotatable about a drive axis in a direction of rotation. This hub part can in principle have any shape. For example, it may be substantially cylindrical. There are also more complex shapes into consideration, for example, the hub part may be wavy in cross section.

From the hub part, two stirring arms extend. These extend radially to the drive axis, i. at least one component of the stirring arms extends radially. However, the stirring arms do not have to be exactly perpendicular to the drive axis as a whole, but can also be inclined at a certain angle to the vertical. Preferably, however, the stirring arms are perpendicular to the drive axis.

The stirring arms have a striking surface. By hitting face is meant herein any face suitable for whipping or stirring dough. In particular, surfaces which are substantially perpendicular to the direction of rotation are possible. The striking surface may be flat or have a concave or convex curvature. Preferably, the impact surface in the vertical direction (ie the direction of the axis of rotation) has an extension of at least 0.1 mm, 0.25 mm or 0.5 mm, whereby expansions of more than 1 mm or 2 mm or 5 mm are also possible but preferably does not exceed the extent of 10 mm or 20 mm.

In accordance with the invention, the stirring tool has at least one inclined surface on each of a striking surface. The striking surface advantageously points up or down, i. The normal of the club face are essentially up or down (but also form an acute angle with the vertical direction).

This can for example form an acute angle with a radial plane. A radial plane is a plane on which the drive axis is vertical. The provision of an inclined surface in turn leads to a better stirring and mixing result. It is believed that the inclined surface helps in the complete comminution of stirring material and that the inclined surface also causes flow in the stirring material, which are beneficial to the mixing.

In particular, when viewed from the direction of the drive axis in the plan view, the striking surface according to the invention describes a bow. As a result, it has various directions of impact. In this case, a direction of impact is to be understood as the normal to a section of the striking surface.

In a preferred embodiment of the invention, a radially inner part of the striking surface now has a direction of impact pointing essentially parallel to the direction of rotation. In contrast, a radially outwardly adjoining part has a substantially perpendicular to the direction of rotation facing direction of impact. In other words, this direction of impact of this part of the striking surface is arranged essentially tangentially to the direction of rotation.

This alignment of a part of the striking surface has surprisingly proved to be advantageous for a favorable mixing result. The exact processes when mixing different doughs are not known and should also depend very much on the particular dough or mix. It is conceivable, however, a "pulling entrainment" of the Rührguts by the striking surface, which is advantageous. Further, the striking surface, even if it is perpendicular to the direction of rotation, exert a certain separating or crushing effect, it seems.

It is also advantageous if the striking surface is continuous. Alternatively, however, the clubface could also consist of various consecutively lined segments or webs. Also, it has proved to be beneficial when the clubface describes an arc. In particular, a face is considered, in which the direction of impact changes over the length of the club face by more than 90 ° or more than 100 °. This is particularly suitable for an arcuate face. Overall, these various embodiments have a good stirring result. This happens even though the face is partially aligned parallel to the direction of rotation. By avoiding the conventional, so to speak frontal beating, however, the stirring tool is more effective and also more torque favorable than a conventional tool.

According to the invention, the stirring tool may also comprise a second stirring arm. (Further, a third, fourth, fifth or further mixing arm would be possible.) This stirring arm should again extend radially in the manner described for the first stirring arm to the drive axis. The second stirring arm likewise has a striking surface which is bent and has different directions of impact, each perpendicular to the striking surface. In an embodiment, the second stirring arm may be radially opposed to the first stirring arm.

The second stirring arm can have substantially the same contour as the first stirring arm, ie the second stirring arm is rotationally symmetrical with respect to the first stirring arm. However, it is also contemplated that the second stirring arm has a different contour than the first stirring arm, ie it is not rotationally symmetrical to the first stirring arm.

In particular, the second stirring arm can be arranged axially higher than the first. It has been shown that the combination of stirring arms of different contour provides better stirring results than two stirring arms of the same contour. This is especially true for axially mounted in different height stirring arms. It is also possible to take into account the mounting height of the stirring arms on the axis in the choice of their contour. In another further attached below Rührarm it seems cheap if he promotes the flow of a flow or mixing direction, which is directed rather upwards, ie away from the bottom of a stirred vessel. For this purpose, it is advantageous if this stirring arm has a large upwardly facing inclined surface.

According to the invention, a second stirring arm can be considered in which the direction of impact changes by less than 100 ° or less than 90 ° due to the length of the striking surface. According to the invention, an inclined surface can also adjoin the impact surface of the second stirring arm, which forms an acute angle with a radial plane. In a stirring tool according to the invention, which has a second stirring arm, the inclined surface of the second stirring arm can point downwards.

According to the invention, any motor driven kitchen appliance with a stirring tool as described herein is also provided. According to the invention there is further provided a method for battering (and / or stirring) dough with a stirring tool of the type described herein.

The stirring tool according to the invention may contain, in addition to the stirring arms described, stirring arms or so-called mixing blades of a different type. In question come, for example, stirring arms or so-called mixing blades short length but large area, which promote the mixing of material to be stirred in the vicinity of the hub part.

The stirring tool can be made entirely of a material. Advantageously, it can be produced by injection molding. Especially plastic, especially polyoxymethylene (POM). Other engineering plastics with good stiffness and good coefficients of friction, which thus can also form a good lower bearing point, can also be used.

The method of whipping dough is advantageously carried out at 800 to 1000 revolutions per minute. Compared to beating dough with other tools a significantly reduced torque is required. This is especially true for hitting heavy doughs. The reference dough may be shortcrust pastry. Beating a reference short pastry dough with a conventional food processor attachment, such as the dough hook of the Braun K700 device, requires up to 1 Nm of torque. However, the inventive stirring tool makes it possible to stir such a dough with a maximum torque of 0.5 Nm.

Fig. 1

eine perspektivische Gesamtansicht des Rührwerkzeuges,

Fig. 2

eine Ansicht des ersten Rührarms von oben,

Fig. 3

eine Schnittansicht des ersten Rührarms, so wie in Fig. 2 gekennzeichnet,

Fig. 4

eine Fig. 3 entsprechende Schnittansicht eines alternativen Rührarms,

Fig. 5

eine Schnittansicht des äußeren Ende des Rührarms aus Fig. 2,

Fig. 6

eine Ansicht des Rührwerkzeugs von unten,

Fig. 7

eine Seitenansicht des Rührwerkzeuges.

• Fig. 1 läßt in perspektivischer Ansicht das Rührwerkzeug 10 und seine Hauptelemente erkennen. Dazu gehört insbesondere das Nabenteil 11. Wie schon in dieser Ansicht erkennbar, ist das Nabenteil in seinem Querschnitt im Wesentlichen wellenförmig gestaltet. Das Nabenteil 11 weist also einen ersten Bogen 12 auf, der in dieser Ansicht konvex auf den Betrachter zu gewölbt ist, und einen sich daran anschließenden zweiten Bogen 13, der in dieser Ansicht konkav ist. Dies erlaubt, mit wenig Material hohe Drehmomente zu übertragen und hat zusätzlich den Effekt, daß auch das Nabenteil einen Beitrag zum Durchmischen von Teig leisten kann. Oben an das Nabenteil 11 schließt sich ein Ring 15 und daran das obere Kupplungsteil 14 an. Mit diesem Kupplungsteil 14 kann das Rührwerkzeug 10 bequem in eine Antriebseinheit eingesetzt werden. Als Antriebseinheit kommt beispielsweise der obere Deckel eines Rührtopfes in Betracht, welcher mit einem Motorteil verbunden ist. Unten erkennt man den ersten Rührarm 20 und gegenüberliegend den zweiten Rührarm 30. Ferner sind um 90° versetzt zur durch die beiden Rührarme definierten Richtung zwei Mischflügel vorgesehen, nämlich ein erster Mischflügel 40 und gegenüberliegend ein zweiter Mischflügel 42. Beim ersten Rührarm 20 erkennt man zum Betrachter hingewandt die Schlagfläche 22. Radial innen liegend ist der Teil 24 der Schlagfläche, während sich der Teil 26 als radial außen liegender Teil anschließt. Der Betrachter blickt auf die Schrägfläche 28, welche sich beim ersten Rührarm 20 an die Schlagfläche 22 anschließt und nach oben gerichtet ist.
• Fig. 2 zeigt den ersten Rührarm 20 in einer Ansicht von oben. Links oben in der Abbildung erkennt man folglich das obere Kupplungsteil 14. Der erste Rührarm 20 weist eine stark gebogene Schlagfläche 22 auf. Diese umfaßt einen radial innen liegenden Teil 24. Die Schlagrichtung des radial innen liegenden Teils 24 entspricht im Wesentlichen der Rotationsrichtung. Anders gesagt, weist eine Normale auf der Schlagfläche in diesem radial innen liegenden Teil 24 in Rotationsrichtung. Wie in der Abbildung deutlich zu erkennen, beschreibt die Schlagfläche 22 einen Bogen. Die Schlagfläche 22 ist also kontinuierlich ausgeführt. Normalen auf die Schlagfläche weisen entlang des Bodens in verschiedene Richtung. Eine Normale auf dem außen liegenden Teil 26 der Schlagfläche weist nicht in die Rotationsrichtung des ersten Rührarms 20, sondern kann sogar radial nach außen weisen, also keinerlei Anteil in Rotationsrichtung haben.

For a better understanding of the invention, the following figures are also intended to serve. Insofar as technical features are presented in a specific combination herein and in the accompanying explanatory text, these are also to be regarded as disclosed individually and in other combinations, insofar as such combinations are technically meaningful and possible. In the pictures show:

Fig. 1

an overall perspective view of the stirring tool,

Fig. 2

a view of the first Rührarms from above,

Fig. 3

a sectional view of the first Rührarms, as in Fig. 2 in

Fig. 4

a Fig. 3 corresponding sectional view of an alternative stirring arm,

Fig. 5

a sectional view of the outer end of the Rührarms Fig. 2 .

Fig. 6

a view of the stirring tool from below,

Fig. 7

a side view of the stirring tool.

• Fig. 1 can be seen in a perspective view of the stirring tool 10 and its main elements. In particular, this includes the hub part 11. As already seen in this view, the hub part is designed in its cross-section substantially wave-shaped. The hub part 11 thus has a first arc 12, which is curved in this view convex to the viewer, and an adjoining second arc 13, which is concave in this view. This allows to transmit high torques with little material and has the additional effect that the hub part can make a contribution to the mixing of dough. At the top of the hub part 11, a ring 15 and the upper coupling part 14 adjoins it. With this coupling part 14, the stirring tool 10 can be comfortably in a drive unit can be used. The drive unit is, for example, the upper lid of a stirred pot into consideration, which is connected to a motor part. Further, 90 ° offset from the direction defined by the two stirring arms two mixing vanes are provided, namely a first mixing blade 40 and opposite a second mixing blade 42. In the first mixing arm 20 can be seen to The viewer turned the impact surface 22. Radially inward is the part 24 of the striking surface, while the part 26 connects as a radially outer part. The viewer looks at the inclined surface 28, which adjoins the impact surface 22 at the first stirring arm 20 and is directed upward.
• Fig. 2 shows the first stirring arm 20 in a view from above. The upper coupling part 14 can be seen on the top left in the figure. The first stirring arm 20 has a strongly curved striking surface 22. This comprises a radially inner part 24. The direction of impact of the radially inner part 24 corresponds substantially to the direction of rotation. In other words, a normal on the impact surface in this radially inner part 24 in the direction of rotation. As can clearly be seen in the figure, the face 22 describes an arc. The striking surface 22 is thus executed continuously. Normals on the clubface point along the ground in different directions. A normal on the outer part 26 of the striking surface does not point in the direction of rotation of the first Rührarms 20, but may even point radially outwards, so have no share in the direction of rotation.

Along the striking surface 22 different normals are drawn on the striking surface, namely the normals N ₁ , N ₂ and N ₃ . N ₁ is located radially inwardly and lies in the inner part 24. N ₁ is oriented substantially in the direction of rotation of the first Rührarms 20. The normal N ₂ is registered in a middle part of the arc which the striking surface 22 describes. It has a component in the direction of rotation and a component perpendicular to the direction of rotation, ie radially outward. The normal N ₃ , which lies in the outer part 26 of the striking surface 22, faces radially outward.

The first stirring arm 20 terminates in an outer end region 27. Especially in this outer end region 27, there is no longer a frontal whipping of stirring material, but at most a kind of "pulling take-away". At the top of the striking surface 22, the inclined surface 28 connects.

• Fig. 4 ist eine der Fig. 3 entsprechende Ansichten. Hier ist jedoch, anders als in Fig. 3, eine relativ breite Schlagfläche 22 gezeichnet. Es schließt sich daran eine nur kurze Schrägfläche 28 an. Eine Schlagfläche, welche flächenmäßig größer ist als die Schrägfläche 28, ist durchaus im Sinne dieser Erfindung. Jedoch kann erfindungsgemäß es auch in Betracht kommen, daß die Schrägfläche 28 flächenmäßig gegenüber der Schlagfläche 22 dominiert.
• Fig. 5 zeigt eine Ansicht eines günstigen äußeren Endbereichs 27 eines Rührarms für das Rührwerkzeug. In diesem alleräußersten Bereich kann die Höhe der Schlagfläche 22 zunehmen. Die Länge und damit die Fläche einer anschließenden Schrägfläche 28 nimmt entsprechend ab. Die Oberkante der Schlagfläche 22 verläuft somit nach außen ansteigend. Diese Geometrie hat sich als vorteilhaft für das effektive Durchmischen von Teig erwiesen. Sie führt im Übrigen auch dazu, daß sich ein Benutzer im Endbereich des Rührarms nicht an scharfen Spitzen und Kanten verletzen kann.
• Fig. 6 zeigt eine Aufsicht auf das Rührwerkzeug 10 von unten. Mittig erkennt man das untere Kupplungsteil, welches als Lagerstelle 16 ausgeführt wird. Die Lagerstelle 16 ist im Wesentlichen als Aufnahme für einen Achsabschnitt ausgebildet sein. Man erkennt ferner den ersten Mischflügel 40 und den zweiten Mischflügel 42 sowie den ersten Rührarm 20 und den zweiten Rührarm 30. Da die Schrägfläche 28 des ersten Rührarms nach oben gerichtet ist, ist sie in dieser Abbildung nicht sichtbar. Sichtbar dagegen ist die Schrägfläche 38 des zweiten Rührarms 30, welche nach unten gerichtet ist. Der zweite Rührarm weist ebenfalls eine Schlagfläche 32 auf, welche von einem radial innen liegenden Teil 34 kontinuierlich und bogenförmig auf den radial außen liegenden Teil 36 hin verläuft. Man kann jedoch erkennen, daß die entsprechenden Normalen keinen so großen Winkelbereich überstreichen wie beim ersten Rührarm 20. Ferner kann man erkennen, daß der zweite Rührarm 30 in seiner Kontur vom ersten Rührarm 20 verschieden ist. (Als Kontur soll hierin der Umriß des Rührarms in der Ansicht von unten gelten.)
• Fig. 7 zeigt eine Seitenansicht des Rührwerkzeugs 20. Als markante Elemente sind wiederum das Nabenteil 11 zu erkennen und der obere Kupplungsteil 14. Ferner erkennt man den ersten Rührarm 20 und den zweiten Rührarm 30 sowie den ersten Mischflügel 40 und den zweiten Mischflügel 42. Die Mischflügel sind entlang der Richtung der Drehachse von gleicher Höhe. Man erkennt an dieser Ansicht ebenfalls besonders gut, daß der erste Rührarm 20 unterhalb des zweiten Rührarms 30 angeordnet ist. (Unterhalb bedeutet hier in Richtung der Rotationsachse gesehen, näher auf die Lagerstelle zu.) Die Anordnung von Rührarmen in verschiedener Höhe hat sich als besonders effektiv für gutes Durchkneten besonders schwerer Teige erwiesen. Dabei ist es vorteilhaft, wenn der untere Rührarm eine nach oben gerichtete Schrägfläche 28 aufweist.

In Fig. 3 recognizes the orientation of inclined surface 28 and striking surface 22 of the first Rührarms 20 once more clear. This illustration shows a section through the first one Stirring arm 20 along the line III-III, as in Fig. 2 marked. In this figure, a normal on the striking surface 22 is shown as N ₄ . It can be seen that the inclined surface forms an acute angle with this normal, which is also in the direction of a radial plane. The normal N ₄ on the inclined surface 28 thus has substantially upwards.

• Fig. 4 is one of the Fig. 3 corresponding views. Here, however, unlike in Fig. 3 , a relatively broad face 22 drawn. This is followed by only a short inclined surface 28. A striking surface, which is larger in area than the inclined surface 28, is well within the meaning of this invention. However, according to the invention, it may also be considered that the inclined surface 28 dominates the surface of the face 22 in terms of area.
• Fig. 5 shows a view of a favorable outer end portion 27 of a stirring arm for the stirring tool. In this extreme area, the height of the clubface 22 may increase. The length and thus the surface of a subsequent inclined surface 28 decreases accordingly. The upper edge of the striking surface 22 thus extends outwardly. This geometry has proven to be beneficial for the effective mixing of dough. It also leads to the fact that a user in the end of the paddle can not hurt on sharp points and edges.
• Fig. 6 shows a plan view of the stirring tool 10 from below. In the middle you can see the lower coupling part, which is designed as a bearing 16. The bearing 16 is essentially designed as a receptacle for an axle section. The first mixing blade 40 and the second mixing blade 42 as well as the first stirring arm 20 and the second stirring arm 30 can also be seen. Since the inclined surface 28 of the first stirring arm is directed upwards, it is not visible in this illustration. Visible, however, is the inclined surface 38 of the second Rührarms 30, which is directed downwards. The second stirring arm likewise has a striking surface 32, which extends continuously and in an arc shape from a radially inner part 34 towards the radially outer part 36. It can be seen, however, that the corresponding normals do not cover as large an angular range as in the first stirring arm 20. It can also be seen that the second stirring arm 30 is different in its contour from the first stirring arm 20. (As a contour herein, the outline of the paddle in the view from below shall apply.)
• Fig. 7 shows a side view of the stirring tool 20. As a striking elements turn the hub part 11 can be seen and the upper coupling part 14. Furthermore, one recognizes the first mixing arm 20 and the second mixing arm 30 and the first mixing blade 40 and the second mixing blades 42. The mixing blades are along the direction of the axis of rotation of the same height. It can also be seen particularly well in this view that the first stirring arm 20 is arranged below the second stirring arm 30. (Below means here in the direction of the axis of rotation, closer to the bearing to.) The arrangement of stirring arms at different heights has proven to be particularly effective for good kneading particularly heavy doughs. It is advantageous if the lower mixing arm has an upwardly directed inclined surface 28.

It can be seen from the figure further that a recess 18 is provided in the hub part 11. This is positioned so that the hub part, despite the material savings achieved by the recess can transmit a high torque.

From the description it has become clear overall how a stirring tool can be produced, with which even heavy doughs can be effectively stirred and which even manages with a drive of low torque.

LIST OF REFERENCE NUMBERS

10

agitator

11

hub part

12

first bow

13

second bow

14

Upper coupling part

15

ring

16

depository

18

recess

20

first mixer

22

Playing surface

24

radially inner part

26

radially outward lying part

27

outer end region

28

sloping surface

30

second mixing arm

32

Playing surface

34

radially inner part

36

radially outward lying part

38

sloping surface

40

first mixing blade

42

second mixing blade

N ₁

Normal on the clubface on part 24

N ₂

Normal on the clubface

N ₃

Normal on the clubface at part 26

N ₄

Normal on the slanted surface

Claims (10)

Agitating tool (10), in particular for dough stirring, with a hub part (12) rotatable about a drive axis in a direction of rotation, from which at least two stirring arms (20, 30) extend radially to the drive axis, each of which has a striking surface (22, 32), characterized in that the stirring arms (20, 30) to the impact surface then each have an inclined surface (28, 38) and this inclined surface (28) on the first stirring arm (20) is aligned upward and the inclined surface (38) on the second stirring arm (30) is oriented downwards. Stirring tool (10) according to claim 1, wherein the striking surfaces (22, 32) each describe an arc. Stirring tool (10) according to claim 1 or 2, wherein the striking surfaces (22, 32) each have different directions perpendicular to the percussion strike directions and in each case a radially inner part (24, 34) of the striking surface a substantially parallel to the direction of rotation facing direction of impact has and a radially outwardly adjoining part (26, 36) has a substantially perpendicular to the direction of rotation facing direction of impact. Stirring tool (10) according to one of the preceding claims, in which the direction of impact changes over the length of the striking surface by more than 90 ° or more than 100 °. Stirring tool (10) according to one of the preceding claims, in which adjoins the impact surface (22, 32) has an inclined surface (28, 38) which forms an acute angle with a radial plane. Stirring tool (10) according to one of the preceding claims, in which the second stirring arm (30) is radially opposite the first stirring arm (20). Stirring tool (10) according to one of the preceding claims, in which the second stirring arm (30) has a different contour than the first stirring arm (20). Stirring tool (10) according to one of the preceding claims, wherein the second stirring arm (30) is arranged axially higher than the first stirring arm (20). Motor-driven kitchen appliance with a stirring tool (10) according to one of the preceding claims. A method of hitting dough with a stirring tool (10) according to any one of the preceding claims.

Images